In UMTS (Universal Mobile Telecommunication System) network, for the purpose of improving the frequency use efficiency and enhancing data rates, HSDPA (High Speed Downlink Packet Access) and HSUPA (High Speed Uplink Packet Access) have been adopted to make the best use of the features of W-CDMA-based system. In this UMTS network, LTE (Long Term Evolution) has been considered for further more enhanced data rates and lower delay (for example, see Non-Patent Literature 1). This LTE system uses, as a multiplexing system, OFDMA (Orthogonal Frequency Division Multiple Access) for the downlink and SC-FDMA (Single Carrier Frequency Division Multiple Access) for the uplink.
In the LTE system, when receiving a signal from a radio base station apparatus, a mobile terminal apparatus demodulates a control signal addressed to itself and controls with use of transmission power control information and scheduling information contained in the control signal. In this case, the mobile terminal apparatus demaps a signal that is mapped to a frequency area within a system band of each system and demodulates the demapped signal, and then, determines whether the signal is addressed to itself or not (blind decoding). Then, it transmits and receives a shared data channel signal in accordance with radio resource allocation information contained in the control signal addressed to itself.
In the 3rd-generation system, generally, the transfer rate of about 2 Mbps at the maximum can be realized for the downlink with use of a 5 MHz fixed band. Meanwhile, in the LTE system, the downlink transfer rate of about 300 Mbps at the maximum and the uplink transfer rate of about 75 Mbps can be realized with use of a variable band of 1.4 MHz to 20 MHz. Besides, in the UMTS network, in order to achieve further broader bands and higher speeds, LTE's successor system has been considered (for example, LTE-A (LTE-Advanced)). In this LTE-A system, for example, the LTE's maximum system band of 20 MHz can be expanded to about 100 MHz.